Circuit breaker including spring closing means with means for moving a charging pawl out of engagement with a ratchet wheel when the spring means are charged

ABSTRACT

A circuit breaker characterized by spring means for closing contacts, means for charging the spring means and including a crank shaft structure, a ratchet wheel rotatably mounted on the shaft, driving pawl means operable to advance the ratchet wheel for charging the spring means, means moving the charging pawl means out of driving engagement with the ratchet wheel when the spring means are charged. Means is also provided to permit movement of the crank shaft structure relative to the ratchet wheel upon discharge of the closing spring.

United States Patent Patel 1 Sept. 5, 1972 [54] CIRCUIT BREAKERINCLUDING SPRING CLOSING MEANS WITH MEANS FOR MOVING A CHARGING PAWL OUTOF ENGAGEMENT WITH A RATCHET WHEEL WHEN THE SPRING MEANS ARE CHARGED[72] Inventor: Nagar J. Patel, Pittsburgh, Pa.

[73] Assignee: Westinghouse Electric Corporation,

Pittsburgh, Pa.

22 Filed: Sept. 16,1971

21 Appl.No.: 181,011

[52] US. Cl. ..200/153 SC, 74/150, 185/40 R, 335/76 [51] Int. Cl ..H0lh3/30 [58] Field of Search...200/153 SC; 335/76, 171, 140; 185/40 R;74/575, 577 R, 149, 150, 154

[5 6] References Cited UNITED STATES PATENTS Shannon ..74/ 150 X Bould..200/153 sc Puzas et a1. ..2oo/1s3 sc Primary Examiner-Robert K.Schaefer Assistant Examiner-Robert A. Vanderhye Att0mey-A. T. Strattonet al.

[57] ABSTRACT A circuit breaker characterized by spring means forclosing contacts, means for charging the spring means and including acrank shaft structure, a ratchet wheel rotatably mounted on the shaft,driving pawl means operable to advance the ratchet wheel for chargingthe spring means, means moving the charging pawl means out of drivingengagement with the ratchet wheel when the spring means are charged.Means is also provided to permit movement of the crank shaft structurerelative to the ratchet wheel upon discharge of the closing spring.

10 Claims, 6 Drawing Figures PATENTED 5197? 3,689,720

SHEET U 0F 6 PATENTEDsEP 5:912

SHEET 5 [IF 6 FIGS J B my I 7 PATENTED EP slsm 3.689.720

' sum 6 BF 6 CIRCUIT BREAKER INCLUDING SPRING CLOSING MEANS WITH MEANSFOR MOVING A CHARGING PAWL OUT OF ENGAGEMENT WITH A RATCHET WHEEL WHENTHE SPRING MEANS ARE CHARGED CROSS-REFERENCE TO RELATED APPLICATION Thisinvention is related to inventions disclosed in the application of N. J.Patel, Ser. No. 770,236, filed Oct. 24, 1968 (now US. Pat. No.3,544,931), of Fred Bould et al., Ser. No. 770,296, filed Oct. 24, 1968(now US. Pat. No. 3,590,192), and of Fred Bould, Ser. No. 874,648, filedNov. 6,- 1961, (now U.S. Pat. No. 3,600,540) and application Ser. No.181,012, filed Sept. 16, 1971.

BACKGROUND OF THE INVENTION 2. Field of the Invention This inventionrelates to a motor operated springclosing circuit breaker and, moreparticularly, it pertains to an improved circuit breaker having springmeans for closing the contacts which spring means are constrained fromoperation by a ratchet wheel and pawl associated therewith.

2.Description of the Prior Art Certain types of circuit breakers areprovided with spring means for closing the circuit breaker contacts. Inthe past, the springs have been charged by a ratchet wheel fixedlymounted on a shaft for charging the springs. For example, in US. Pat.No. 3,254,186, a ratchet wheel is mounted on a crank shaft for chargingsprings for closing the circuit breaker contacts. Discharge of thesprings is prevented only by the ratchet wheel and a holding pawl. Onedisadvantage of that type of structure has been'chipping and breakage ofthe ratchet wheel teeth particularly during free discharge of springs.

Various attempts to overcome that disadvantage have been made includinga ratchet wheel which is rotatably mounted on shaft and disengaged fromthe charging spring system during the discharge thereof. The ratchetwheel has been provided with a'so-called missing tooth portion which hadthe effect of disengaging the charging pawl from the ratchet wheel whenthe spring means are completely charged. This in turn incurs adisadvantage in that the ratchet wheel turned by random amounts resultsin the holding pawl or charging pawl engaging the missing tooth portioninstead of the toothed portion of the ratchet wheel upon subsequentcharging of the spring means. Accordingly, the use of a ratchet wheelwhich is rotatably mounted on a charging shaft and having a missingtooth portion does not completely satisfy the disadvantages of chippingand breakage of ratchet wheel teeth. The US. Pat. No. 2,961,067discloses a ratchet wheel with a missing tooth portion.

SUMMARY OF THE INVENTION It has been found in accordance with thisinvention that the foregoing problems may be overcome by providing aratchet wheel which is rotatably mounted on a crank shaft and having nomissing tooth" portion. In conjunction with clutch means including acharge plate fixedly mounted on the charge shaft and rotatable with theratchet wheel when actuated by pin means extending from the ratchetwheel. The ratchet wheel is disengaged from the charged plates through arotation of about 330,-thus preventing any movement of the ratchet wheelduring discharging of the springs. Finally, the charge plates includecamming edges for disengaging the charging pawl from the ratchet wheelwhen the spring means are in the charged position.

The advantage of the improved charging system for circuit breakers ofthis invention is not only the avoidance of the problem of breaking andchipping ratchet teeth but also the provision of a positive-actingclutch that disengages the reciprocating charging pawl when the springsare in the fully charged position and, thereby preventing damage to theteeth for any reason, such as failure of the charging motor to shut offwhen necessary. A further advantage is that the charge plates are freeto rotate through approximately 330 (as compared with only in presentconstructions), thereby providing positive disengagement of the ratchetwheel from the charge plates and shaft which rotate and oscillate aboutthe spring dead center during the discharge of associated spring means.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an end view with partsbroken away and certain parts omitted for clarity of a circuit breakerconstructed in accordance with this invention;

FIG. 2 is a sectional view taken generally along the line II-Il of FIG.1;

FIG. 3 is a partial sectional view taken generally along the lineIII-III of FIG. 1 with the crank shaft and the closing spring shown inthe charged position;

FIG. 4 is a partial sectional view with parts broken away and showingthe crank shaft and closing spring in the discharged position;

FIG. 5 is an enlarged framentary end view of the spring chargingmechanism; and

FIG. 6 is an exploded isometric view of thespring charging mechanismwith the spring in the charged position.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, thereis shown in FIGS. 1 and 2 a three-pole circuit breaker 5 comprising asupport structure or housing 7 and a circuit breaker structure 9supported on the housing structure. The housing structure 7 comprises ametallic base plate 11, a pair of spaced metallic side plates 13 fixedlysecured to flanges of the base plate, a pair of metallic center plates17 fixedly mounted on the base plate, and a back wall structureindicated generally at 19.

The circuit breaker structure 9 is a three-pole structure comprising astationary contact 21 (FIG. 2) and a movable contact 23 for each poleunit. Each of the movable contacts 23 is supported on a conductingcontact arm 25 that is pivotally supported on a terminal conductor 27 bymeans of a-pivotal support means 29. In each pole unit, a separateinsulating connecting member 31 is pivotally connected at one endthereof to the contact arm 25 and at one end thereof to the contact arm25 and at the center end thereof a lever 33 that is welded to a commonjack shaft 35 that extends across all of the poles of the circuitbreaker. There is a separate lever 33 for each pole unit welded to thecommon jack shaft 35. Only one of the contact structures is shown inFIG. 1. The contact structures for the center pole and for the left-handpole (FIG. 1) are omitted from he drawing in FIG. 1 merely for clarity.It can be understood that the contact structures for all three poleunits are the same as the one contact structure shown in FIGS. 1 and 2.

The jack shaft 35 is supported for pivotal movement, about the elongatedaxis thereof, on the side plates 13 and center plates 17. The connectingmember 31,

levers 33, and jack shaft 35 are part of a stored-energy spring-closingmechanism 39 that is operable to close the contacts 23, 21. Themechanism 39 comprises a link 41 that is pivotally connected, at one endthereof, to the lever 33 of the center pole by means of a pin 43. Thelink 41 is pivotally connected at the other end thereof, to a link 45 bymeans of a knee pivot pin 47. A roller member 49, that serves as a camfollower, is mounted on the pin 47 to cooperate with a closing cam 51.The link 45 is pivotally connected at the other end thereof to a latchmember 53 by means of a pin 55. The latch member 53 is mounted forpivotal movement about a fixed pivot pin 57 that is supported on thelefthand (FIG. 1) center plate 17. A tension spring 59 is connected tothe pin 55 to reset the linkage following a tripping operation of thecircuit breaker. The latch member 53 engages the periphery of a tripshaft 63 in proximity to a cut-out portion of the shaft 63, whichcut-out portion is provided so that when the trip shaft 63 is rotated ina counterclockwise direction the latch member 53 will be free to moveinto the cut-out portion to the tripped position. The trip shaft 63 issupported for pivotal movement about the elongated axis thereof betweenone of the center plates 17 and one of the side plates 13.

A roller latch 67 (FIG. 2) is rotatably supported on and between thetwin plates of the closing shaft 71 that is rotatably supported onsuitable bearings that are secured to the center plates 17. A pair ofcrank arms 73 are fixedly mounted on the crank shaft 71 at the oppositeends of the crank shaft.

As shown in FIGS. 3 to 6 a ratchet member or wheel 74 is rotatablymounted on the crank shaft 71, as evidenced by a circular hole 74a. Apair of charge plates 75 and 76 are fixedly mounted on the crank shaft71 and on opposite sides of the ratchet wheel 74. The plates 75 and 76include the strike surfaces 75a and 76a, respectively, as well as thecamming surfaces 75b and 76b, respectively. A projection or pin 77having opposite end portions extending from opposite sides of ratchetwheel 74 are disposed in the paths of travel of the strike surfaces 75aand 76a. The crank shaft 71, crank arms 73, and plates 75, 76, move inunison as a crank shaft structure 77a. A reciprocable member 78 isrotatably mounted on crank shaft 71 where it is supported for pivotalreciprocating movement relative to the crank shaft to cooperate with theratchet wheel 74 and charge plates 75 and 76.

As the member 78 turns the ratchet wheel 74 counterclockwise (FIG. 4)the pin 77 (bearing against the strike surfaces 75a and 76a) rotate thecharge plates 75 and 76 and hence the crank shaft 71 is turned from thedischarged position (FIG. 4) to the charged position (FIG. 3). When thecharged position is reached, the camming surface 76b lifts the lever 111(FIG. 6) and the charge pawl 107 is disengaged from the ratchet 74. Oncethe charge plates reach the charge position as shown by the broken lineposition 76a (FIG. 3), the tension in the springs 79 is sufficient torotate the pin 80 below a line through the axes of the shaft 71 and therod 82 to the solid line position of the plates. This action is arrestedwhen the latch roller 67 strikes the member (FIG. 2).,

A separate tension spring 79 is operatively connected at the end of eachof the crank arms 73 by means of a pivot pin 80. Each of the springs 79is connected to a spring support 81 that is pivotally connected to theassociated arm 73 by means of the associated pivot pin 80. Each of thetension springs 79 is connected, at the other end thereof, to a rod 82that is secured to the center plate 17. A manual operating mechanism,indicated generally at 83 (FIG. 1), is provided for manually chargingthe closing springs 79. A latch member 85 (FIG. 2) is pivotally mountedon a pin 87 and biased in a clockwise (FIG. 2) direction to the latchingposition wherein the latch 85 engages the roller 67 to latch the closingcam 51 and crank shaft 71 to prevent counterclockwise movement of theclosing cam 51 and crank shaft 71.

The circuit breaker is shown in FIG. 2 in the contact open position withthe stored energy closing springs 79 in the charged condition. As isshown in FIG. 2, the spring support pins 80 of the tension springs 79are below a line between the center of the spring support rod 82 and thecenter or axis of the crank of shaft 71 so that the charged tensionsprings 79 are operating to bias the crank shaft 71 in acounterclockwise direction. Counterclockwise movement of the crank shaft71 is prevented by the engagement of the latch member 85 with the latchroller 67 that is mounted on the closing cam 51. The latch member 85 isoperated to the unlatching position to close the circuit breaker in amanner described in the above-mentioned Pat. No. 3,590,192.

When it is desired to close the breaker, the latch 85 is pivoted in acounterclockwise (FIG. 2) direction to thereby release the roller 67.When the roller 67 is released, the closing cam 51 and the crank shaft71 are free to rotate in a counterclockwise direction, and the closingsprings 79, operating on the crank arms 73, operate to rotate the crankshaft 71 in a counterclockwise direction as the spring 79 discharge.During this movement, the closing cam 51 will force the roller 49, andthe link 41 upwardly to the closed position. During this closingmovement of the link 41, of the lever 33 (FIG. 2) of the center poleunit is forced in a counterclockwise direction to rotate the jack shaft35 counterclockwise to simultaneously move the three contact arms 25 ina clockwise direction about the pivots 29 to the closed position. In theclosed position, the engagement of the closing cam 51 with the roller 49serves to prop the link member 41 in the closed position to therebymaintain the jack shaft 35 and contacts 23 in the closed position.

With the contacts in the closed position and the closing spring 79discharged, the circuit breaker may be automatically tripped open, inresponse to an overload above a predetermined value in any of the poleunits, by operation of the trip shaft 63 in a manner described in the U.S. Pat. No. 3,544,931. During the tripping operation, the trip shaft 63is rotated in a counterclockwise (FIG. 2) direction. When the trip shaft63 is rotated counterclockwise, the trip shaft moves to permit the latchmember 53 to move into the cut-out portion of the trip shaft 63, therebypermitting the latch member 53 to move in a counterclockwise directionabout the pivot 57 to the tripped position. The compressed contactsprings 93 (FIG. 2) and an opening spring 99 (FIG. 1) then operate tomove the contact arms 25 toward the open position which movement occursbecause the pivot 55 is free to moveso that the link 45 can move to thetripped position with the toggle 45, 41 collapsing to permit the lever33 and jack shaft 35 to move in a clockwise direction to the trippedopen position. Thus, movement of the trip shaft 63 to the trippedposition permits the members 41, 45, 53 to move to the tripped position,wherein the roller 49 and link 41 no longer restrain the lever 33 in theclosed position, and the springs 93, 99 operate to move the jack shaft35 and the three contact arms 25 to the tripped open positions.

With the circuit breaker in the tripped open position, the breaker isreset and the closing springs 79 are charged by operation of themotor-drive structure 101 in a manner to be hereinafter morespecifically described. In order to reset the circuit breaker and chargethe closing springs 79, the crank arm 73 is rotated from the springdischarged position of FIG. 4 through an angle of more than 180 to thespring charged position of FIGS. 2 and 3. As the crank shaft 71 moves tothe position seen in FIG. 2, the roller 49 rides off of the peak of thecam 51 into the depression seen in FIG. 2. When the roller 49 is free tomove into the depression of the cam 51, the spring 59 (FIG. 1) biasesthe latch 53 clockwise (FIG. 2) to move the latch 53 to the resetposition pulling links 45, 41 and the roller 49 to the reset positionwherein the roller 49 is positioned in the depression of the cam 51(FIG. 2). When the latch 53 moves out of the notch of the trip shaft 63,suitable spring means operates to rotate the trip shaft 63 clockwise tothe latching position wherein the periphery of the trip shaft 63 againlatches the latch member 53 to latch the parts in the reset positionseen in FIG. 2. As the crank shaft 71 moves more than 180 to theposition seen in FIGS. 2 and 5 the springs 79, which are movedover-center, take over to bias the crank shaft 71 in a counterclockwise(FIG. 2) direction, and the roller 67 engages the latch 85 to latch thecrank shaft 71 in the charged position seen in FIG. 2, and the circuitbreaker is prepared for another closing operation.

When the circuit breaker is in the contact-closed position with thestored energy closing springs 97 discharged the spring closed means isoperated to the charged position by operation of the motor drive structure 101 (FIG. 5) to rotate the crank shaft 71 through an angle ofslightly more than 180 (approximately l84to charge the springs 79 duringwhich movement the roller 49 rides on a fixed radius of the cam 51 to aposition just short of the peak of the cam surface of the cam member 51.This charging movement of the cam 51 is more specifically described inthe above-mentioned US. Pat. No. 3,590,192.

With the parts in the contact closed spring charged position, thefollowing sequency of operations can occur.

Upon the occurrence of an overload above a predetermined value, the tripmeans indicated generally at 95 (FIG. 1) is automatically operated torotate the trip shaft 63 to release the latch member 53 and permit thetoggle 41, to effect an opening operation in the same manner as washereinbefore described. With the toggle 41, 45 collapsed, the spring 59operates to draw the roller 49 into the depression of the cam 51resetting the linkages 53, 41, 45 and the trip shaft 63 is moved byspring means into the latching reset position seen in FIG. 2. The partsat the end of this tripping operation are in the position seen in FIG.2, wherein the mechanism is reset and relatched, and wherein the rollermember 49 is in the depression of the cam 51 so that the parts areprepared for a closing operation. When the closing springs 79 arecharged, an operator can immediately operate the closing latch 85 (FIG.2) to release the roller 67 whereupon the circuit breaker is operated tothe closed position in the same manner as was hereinbefore described.With the parts in the closed position, if an overload above thepredetermined value occurs the trip means 95 will be automaticallyoperated to rotate the trip shaft 63 to the stripped position to effecta tripping operation in the same manner as mentioned before described.With the parts in the tripped position and the closing springs 79discharged, another charging operation of the closing springs 79 will berequired in order to provide another closing operation. Thus, when thecircuit breaker is in the contact closed spring charged position, thecircuit breaker can be tripped and then closed and then tripped again inrapid sequence.

The reciprocating member 78 (FIGS. 3 to 6) comprises a circular opening105 and a flange or bight portion 106. The reciprocating member 78 isrotatably mounted on the crank shaft 71 for movement relative to thecrank shaft about the axis thereof. A charging pawl 107 also ispivotally mounted on the oscillating member 78 by means of a pin 108,and a torsion spring 109 biases the pawl 107 in a counterclockwisedirection about the pin 108 into engagement with the ratchet wheel 74.The pawl 107 also includes a lever 11] as an integral part which leverhas an end portion 112 that is contacted and lifted by the cammingsurface b when the charge plate 75 is in the charge position (FIGS. 3and 6), whereby the pawl 107 is raised out of operation with the ratchetwheel teeth. A tension spring member 113 biases the reciprocating member78 in a clockwise direction (FIG. 3) about the crank shaft 71. A holdingpawl 114 is pivotally mounted on one of the center plates 17 by means ofa pin 115 and biased in a counterclockwise direction, by means of atorsion spring 116, into engagement with the ratchet wheel 74.

The drive motor 101 comprises an output shaft 133 (FIG. 5). An arm 137is mounted on the end of the shaft 133 and a roller member 139 isrotatably mounted on a pin 141 that is supported on the arm 137.

As can be seen in FIG. 3, the closing springs 79 are in the chargedposition with the closing latch 85 (FIG. 2) engaging the roller 67 ofthe cam 51 to latch the crank shaft 71 in the spring charged positionshown in FIG. 3. Upon the release of the latch 85, the springs 79discharge rotating the crank shaft 71 slightly more than to close thecircuit breaker in a manner hereinbefore described. Upon discharge ofthe closing springs 79 suitable limit'switch means is actuated in a wellknown manner by the breaker mechanism to energize the drive motor 101.Upon energization of the drive motor 101, the arm 137 is rotated in aclockwise (FIG. 3) direction about the axis thereof at a suitable ratesuch as 500 rpm.

During each revolution of the output shaft 133 the roller 136, operatingagainst the bight part 107 of the oscillating member 78 moves theoscillating member in a counterclockwise direction during which movementthe driving pawl of 109 operates against one of the teeth of the ratchet74 to advance the ratchet and crank shaft 71. As the roller arm 137moves 180' from the position seen in FIG. 4, the member 78 will advancethe ratchet 74 and crank shaft 71 in a counterclockwise direction, andas the roller arm 137 moves the remaining 180 of a 360 revolution, thespring 113 will return the member 78 to the position seen in FIG. 3 withthe holding pawl 121 holding the ratchet 74 and crank shaft 71 in theadvanced position. Thus, as the output shaft 133 rotates, the ratchet 74is advanced by the charging pawl 107 and alternately held by the holdingpawl 114 until the crank shaft 71 moves more than 180 to an over-centerposition wherein the charged closing springs 79 again bias the crankshaft 71 in a counterclockwise direction with the ratchet 74 and crankshaft 71 becoming latched from closing movement by the latch member 85(FIG. 2) which engages the roller 67 on the cam 51 that is fixed to thecrank shaft 71. When the closing springs 79 reach the fully chargedposition, the charging pawl 107 is disengaged from the teeth (FIG. 3) ofthe ratchet 74 so that continued rotation of the motor will not operateagainst the teeth of the ratchet 74, and the motor can be brought to astopped condition without damaging the parts and without putting undueforces on the parts. The motor 101 is automatically deenergized bysuitable limit switch means in a manner well known in the art.

Upon release of the springs 79, the charge plates 75 and 76 stopultimately at the position shown in FIG. 4 whereas the pin 77 remains inthe same position. When the springs reach the discharged position (FIG.4), the pivot pin 80 overshoots the dead center position due to the highvelocity developed and then oscillates clockwise and counterclockwisewith reducing amplitudes until the energy is completely dissipated.However, the ratchet 74 remains stationary and undisturbed by thedischarge operation as noted by the similar position of the pin 77 inFIGS. 3 and 4.

What is claimed is:

1. A circuit breaker comprising a pair of contacts operable between openand closed positions, a crank shaft structure, closing spring meansconnected to said crank shaft structure, a ratchet wheel movable to movesaid crank shaft structure from a spring discharged position to a springcharged position to charge said closing spring means, releasable latchmeans latching said crank shaft structure in said spring chargedposition, a reciprocating drive pawl structure in driving engagementwith said ratchet wheel, operating means operable to reciprocate anddrive pawl structure to move said ratchet wheel to thereby move saidcrank shaft structure from said spring discharged position to saidspring charged position, and disengaging means operating automaticallywhen said crankshaft structure is moved to said spring charged positionto move said drive pawl structure out of driving engagement with saidratchet wheel.

2. A circuit breaker comprising a pair of contacts movable relative toeach other between opened and closed positions, closing spring meansoperable to a charged condition for moving the contacts to the closedposition, means for charging the spring means and including a crankshaft and a ratchet rotatable with respect to the crank shaft, rotatablemeans fixedly mounted on the crank shaft, projection means on andextending from the ratchet, a portion of the rotatable means beingdisposed in the path of travel of the projection means, the chargingmeans also including a reciprocating charge pawl operable to advance theratchet for charging the closing spring means, holding pawl means forconstraining the ratchet, means on the rotatable means for disengagingthe charge pawl when the closing spring means are in the chargedcondition, means for releasing the closing spring means from the chargedcondition and operatively connecting the spring means with at least oneof the contacts for moving the contacts to the closed position.

3. The circuit breaker of claim 2 in which the ratchet is a wheelrotatable on the axis of the crank shaft.

4. The circuit breaker of claim 3 in which the ratchet wheel isrotatably mounted on the crank shaft.

5. The circuit breaker of claim 2 in which the projection means is a pinextending from one side of the ratchet wheel.

6. The circuit breaker of claim 5 in which the pin is disposed in anaxis substantially parallel to that of the rotation of the ratchet.

7. The circuit breaker of claim 2 in which the rotatable means is acharge plate.

8. The circuit breaker of claim 7 in which the plate includes a strikesurface in the path of travel of the projection means.

9. The circuit breaker of claim 2 in which the rotatable means is aplate and in which the disengaging means is a cam surface operable tolift the charge pawl out of engagement with the ratchet.

10. The circuit breaker of claim 2 in which the projection means extendfrom opposite sides of the ratchet, in which the rotatable means includea plate on opposite sides of the ratchet, in which the ratchet is awheel rotatable mounted on the crank shaft, and in which each plate hasa cam surface operable to disengage the drive pawl from the ratchetwheel.

1. A circuit breaker comprising a pair of contacts operable between openand closed positions, a crank shaft structure, closing spring meanscoNnected to said crank shaft structure, a ratchet wheel movable to movesaid crank shaft structure from a spring discharged position to a springcharged position to charge said closing spring means, releasable latchmeans latching said crank shaft structure in said spring chargedposition, a reciprocating drive pawl structure in driving engagementwith said ratchet wheel, operating means operable to reciprocate anddrive pawl structure to move said ratchet wheel to thereby move saidcrank shaft structure from said spring discharged position to saidspring charged position, and disengaging means operating automaticallywhen said crank shaft structure is moved to said spring charged positionto move said drive pawl structure out of driving engagement with saidratchet wheel.
 2. A circuit breaker comprising a pair of contactsmovable relative to each other between opened and closed positions,closing spring means operable to a charged condition for moving thecontacts to the closed position, means for charging the spring means andincluding a crank shaft and a ratchet rotatable with respect to thecrank shaft, rotatable means fixedly mounted on the crank shaft,projection means on and extending from the ratchet, a portion of therotatable means being disposed in the path of travel of the projectionmeans, the charging means also including a reciprocating charge pawloperable to advance the ratchet for charging the closing spring means,holding pawl means for constraining the ratchet, means on the rotatablemeans for disengaging the charge pawl when the closing spring means arein the charged condition, means for releasing the closing spring meansfrom the charged condition and operatively connecting the spring meanswith at least one of the contacts for moving the contacts to the closedposition.
 3. The circuit breaker of claim 2 in which the ratchet is awheel rotatable on the axis of the crank shaft.
 4. The circuit breakerof claim 3 in which the ratchet wheel is rotatably mounted on the crankshaft.
 5. The circuit breaker of claim 2 in which the projection meansis a pin extending from one side of the ratchet wheel.
 6. The circuitbreaker of claim 5 in which the pin is disposed in an axis substantiallyparallel to that of the rotation of the ratchet.
 7. The circuit breakerof claim 2 in which the rotatable means is a charge plate.
 8. Thecircuit breaker of claim 7 in which the plate includes a strike surfacein the path of travel of the projection means.
 9. The circuit breaker ofclaim 2 in which the rotatable means is a plate and in which thedisengaging means is a cam surface operable to lift the charge pawl outof engagement with the ratchet.
 10. The circuit breaker of claim 2 inwhich the projection means extend from opposite sides of the ratchet, inwhich the rotatable means include a plate on opposite sides of theratchet, in which the ratchet is a wheel rotatable mounted on the crankshaft, and in which each plate has a cam surface operable to disengagethe drive pawl from the ratchet wheel.